Chris Marshall's site providing a brief summary of all major roads in the UK. It is beautifully illustrated and includes a commentary on each road

The UK Roads Portal

The "umbrella" site of the SABRE (Society for All British Road Enthusiasts) Group. It links to all the main British roads sites listed here, and includes a "road search" facility, allowing easy access to the description of (nearly) every numbered road in Great Britain

UK Roads

Another interesting site associated with SABRE. This gives a different slant to the lists, including topics such as "lost Motorways", "Near-motorways", "Railways to Roads" etc